Current progress in miniaturization, nanotechnology, and nanolithography is not only limited by the scientific community's ability to put ideas into action. It can also be limited by the ability to test those new ideas and furthermore to test the actual devices that are fabricated from the bottom up. In the case of nano-scale electronic device fabrication, it can be difficult to integrate the nanoscale components with traditional microscale testing environments. Commercially available, systematically structured devices for application and testing of nanoscale experiments are generally unavailable. Rather, researchers are forced to design photomasks and fabricate their own substrates and to use expensive electron beam equipment to build circuit test rigs.
In addition to academic research, a commercial need exists for researchers and engineers to better understand small scale circuits, be they microcircuits or nanocircuits. For example, an important segment of commercial nanotechnology is the rapidly developing ability to generate nanocircuitry through use of nanotubes, nanowires, nanorods, and other nanostructures including those having semiconducting and conducting electrical properties. Carbon nanotubes are of particular interest. Once these nanocircuits are formed, however, a commercial need exists for connecting the nanocircuitry to the larger world, especially existing methods used to test circuits. For example, electrical measurements on the nanostructures and their nanocircuits are needed which are compatible with existing technology. It can be difficult, however, to connect the larger world of electrical measurements with small-scale circuits, particularly nanocircuits, using existing technology which is readily available. A strong commercial need exists, therefore, for devices to solve this problem in practical, commercial engineering as well as academic research.
Small-scale circuits, including nanocircuitry, can be formed by lithography including nanolithography. One important lithographic method is the direct-write type being developed at Northwestern University and NanoInk, Inc. under the proprietary trademark, DIP PEN NANOLITHOGRAPHY™ (DPN™) printing. In this direct-write nanolithographic method, a tip is used to deposit a patterning ink on a substrate, forming a stable nanostructure. Any devices developed for electrical measurements on nanocircuitry should, if possible, be compatible with nanolithgraphic methods. For example, value is increased if a nanocircuit can be formed on a substrate by nanolithography and then the electrical characteristics can be measured directly on the same device used for the nanolithography. A need exists for better, lithography substrates which provide for measurements of the nanostructures formed on the substrate.
The present invention defines a sample substrate tool which enables the nanotechnologist, whether engaged in academic research or commercial production, to systematically build nanoscale devices and then seamlessly test them in situ.